a. Field of the Invention
The present invention relates generally to window cover systems and, in particular, to an improved hinge suitable for use in window cover systems and to window cover systems using the hinge.
b. Definitions and Applicability
As used here, the word "blind" refers to slat structures such as so-called venetian (horizontal slat) blinds, or vertical slat blinds, or so-called mini-blinds, to single and multiple pleat folding structures, and to flat, sheet structures such as the covers used in roller blinds. "Blind" may also refer to box, hollow and cellular pleat structures. In this document, "blind" and "cover" frequently are used generically, in that "cover" includes "blind" and vice versa. It is believed which meaning is intended--the generic or the specific--will be apparent from the context. The terms "box" pleat blind, "hollow" pleat blind and "cellular" pleat blind are used interchangeably. Also, here the words "carrier," "trolley" and "roller" are used interchangeably.
The present invention is applicable generally to vertically oriented window cover systems, primarily to slatted covers, but also to pleated, and to cellular pleat covers. It is understood that "window," as used for example in "window covers," includes windows, doorways, openings in general and even non-opening regions to which "window covers" are applied for decoration, display, etc.
c. Current State of the Relevant Field
Covers such as vertical slat blinds typically are difficult to control, because the cover comprises individual slats which should be maintained in the desired vertical orientation during operation of the blind. The operation of such blinds may include sliding the array of slats which comprise the blind open and closed along the horizontal direction and pivoting the individual slats open and closed in unison about vertical axes through each slat.
Conventional control systems opt for simplicity, which reduces control, or for control, which requires cumbersome apparatus. For example, in one simple approach, the slats are mounted at their upper ends to carriers or trolleys, etc. which in turn are mounted for traversing movement along a track which contains mechanisms for traversing the slats horizontally and pivoting the slats. Due to their unrestrained lower ends, it is virtually impossible to maintain the alignment of the slats, which tend to wave and to undulate in the slightest air current and when the blinds are being opened or closed.
Some systems are designed to more precisely control the movements of traversable slats by mounting the lower end of the slats in a bottom traverse track. Typically, the traversing and pivoting operations of the slats are controlled from one end of the slats, from the top traverse track, with the result that control is imperfectly transmitted along the slats and the bottom ends tend to bind in the lower traverse track. Furthermore, and in particular when used indoors, the lower traverse tracks are an obstruction unless mounted in a recess, and quickly accumulate dirt, thus presenting an unpleasing appearance and tending to bind during operation.
Conventional vertical slat blind systems also have shortcomings concerning privacy. Such systems require a choice between privacy and illumination. Thus, in a room having windows and/or doors covered by slat blinds, occupants of the room are afforded complete privacy only when the blinds are completely closed (and if the blinds maintain their position, that is, if the blinds do not move or undulate). Clearly, when the slat blinds are completely closed and maintain their closure, they block sunlight from illuminating the room via the windows. Conversely, if a blind is opened to some degree to admit daylight, occupants or contents of the room may be visible to an external observer through the window, to a degree determined by the inclination and spacing of slats in the blind and the distance of the observer from the window.
There is a need for a vertical slat blind type of window cover system which is simple in construction, yet maintains the selected positioning and orientation of the individual slats and the array. In addition, there is a need for a cover system which affords privacy for occupants of a room, while still retaining the ability to provide an illumination control function, that is, to permit illumination without loss of privacy. Such a system should also be characterized by low cost and by ease of installation and maintenance, and should be pleasing in appearance.